by Mark Edwards

There is growing evidence that conventional pesticides have increased the prevalence of autism spectrum disorder.

There is growing evidence that conventional pesticides have increased the prevalence of autism spectrum disorder.

The last post positioned algae solutions for bioremediation of poisoned water and soil that can reduce the risk of arsenic exposure and the onset of autism spectrum disorder, (ASD). This essay explores how algae bioproducts can serve directly as medicines to reduce the symptoms and severity of ASD.

Autism is the fastest-growing serious developmental disability in the U.S. Autism prevalence has grown 123% since records began in 2002. The CDC estimates that one in 68 children has been diagnosed with ASD. One person is diagnosed with ASD every 20 minutes. ASD costs the US over $137 billion per year, a figure expected to significantly increase in the next decade.

Autism costs a family $60,000 a year on average. Boys are nearly five times more likely than girls to have autism, but scientists do not know why. There is currently no medical detection or cure for autism.

Autism spectrum disorder causes significant social, communication and behavioral challenges. People with ASD look the same as others but people with ASD may communicate, interact, behave, and learn in ways that are different from most other people. The learning, thinking, and problem-solving abilities of ASD people can range from gifted to severely challenged. Many people that suffer from ASD need considerable help in their daily lives. ASD occurs in all racial, ethnic and socioeconomic groups.

A series of three studies at the University of California-Davis MIND Institute reported increased rates of autism among the children of women who lived close to pesticide-treated fields during pregnancy. The association was strongest when the exposures occurred during the second and third trimesters.

Pesticides are designed to kill pests but their targets ingest less than 1% of the pesticides. The residual pollutes the farm ecosystem and adheres to food. People living near farms that use pesticides have increased vulnerability to a host of neurological diseases. The most vulnerable are pregnant mothers, developing fetuses, young children and the elderly.

Pesticide warnings may keep people from the field but not the neighborhood

Pesticide warnings may keep people from the field but not the neighborhood

Over 70% of the insecticides applied in the U.S. are organophosphorus (OPs), which were developed by German Scientists during WWII as nerve agents. These compounds use the same action mechanism as sarin nerve gas that blocks the nervous system of insects, which scramble their brains. When insect brains are disrupted, the bugs die, which is great for farmers. OPs are derivatives of phosphoric acid and have replaced the banned organochlorine compounds, where their toxicity lasted too long after application. The over 10,000 OPs on the global market vary substantially in toxicity, residue levels and excretion.

OPs interfere with the animal and human nervous systems, even with low exposure. Other adverse health effects of individual OP pesticides occur too; some are acutely toxic, some cause development or reproductive harm and others are known endocrine disruptors. Some pesticides deliver all three threats.

OPs block cholinesterase from its primary job, which is signaling the brain. The pesticide may enter the body through ingestion, inhalation or contact with eyes or skin. Cholinesterase is an enzyme in the human nervous system that breaks down acetylcholine, a neurotransmitter that carries signals between nerves and muscles. When cholinesterase is inactivated, acetylcholine builds up in the nerves and becomes overactive. Victims of organophosphate poisoning typically die because they cannot breathe. It is a painful way to die because the victim suffocates because the muscles are essentially paralyzed. Twelve children died of OP poisoning after a school lunch in India in 2013.

Worldwide, an estimated 3,000,000 people are exposed to organophosphate or carbamate agents each year, with up to 300,000 fatalities. The CDC reports an average of 23 deaths occur each year with pesticides as the underlying cause of death. Pesticide deaths are hugely underreported as the symptoms and deaths mask the source. The American Association of Poison Control Centers estimates pesticide emergency department visits, hospitalizations, and health care costs of $200 million annually. The National Pesticide Information Center reports pesticides are responsible tens of thousands of animal deaths are year.

(L) Pesticide application by hand, (R) Airplane application

(L) Pesticide application by hand, (R) Airplane application

The CHARGE study

A team of researchers combined data from the Childhood Autism Risks From Genetics and the Environment, (CHARGE) study with data from the California Pesticide Use Report. The team investigated how exposure to pesticide drift from spray on nearby fields contributed to autism spectral disorders and developmental difficulties among mothers’ soon-to-be-born children.

The CHARGE study led by Janie F. Shelton at U.C. Davis and a U.N. consultant, compared insecticide exposure from 1997 to 2008 with mental health metrics of the children of nearly 1,000 mothers in California where 200 million pounds of insecticides are sprayed every year.

About a third of the mothers in the study lived, during their pregnancy, within 5,000 feet of a farm where one of the four pesticide classes being studied were sprayed. These mothers were substantially more likely to have kids with autism or kids who suffer difficulties developing communication, social, and motor skills. These problems affect one out of every 25 American children.

Children with autism spectral disorders were found to have had a 60% greater chance of having had organophosphates sprayed near their mothers’ homes while they were still in the womb. Children with development disorders were nearly 150% more likely to have had carbamate pesticides applied near the home during their mothers’ pregnancy. Both of the associations grew stronger as the pesticide applications encroached more closely upon their mothers’ homes.

This research shows that applications of two of the most common agricultural pesticides, (organophosphates and pyrethroids), near the home increases the prevalence of ASD. Pesticides are neurotoxic and the tender neuron networks in small children are particularly vulnerable to disruption. The organophosphates function by hyperexciting neuronal synapses. They make neurons fire faster than normal. During child development, these flash-firing neuronal synapses create a thunderstorm of neural activity that is catastrophic to the developing brain.

Autism creates a thunderstorm of neural brain activity

Autism creates a thunderstorm of neural brain activity

Pesticides are ubiquitous in modern industrial agriculture. Pesticides put not only producers and consumers at severe health risk but also threaten rural communities.

Algae solutions

Algae offer two medical solutions to the pesticide residues linked to ASD.

  1. Some algae species contain compounds that can operate as cholinesterase inhibitors and allow infant brains to develop and operate normally.
  2. Other algae compounds moderate the symptoms of ASD.

Algae have the potential to produce cholinesterase inhibitors and other compounds that may help developing brains advance normally. No algae producers have announced production of algae-based cholinesterase inhibitors – yet.

Cholinesterase inhibitors, also called acetylcholinesterase inhibitors, lower or stop the acetylcholinesterase enzyme from breaking down acetylcholine. This enhances brain signaling by increasing both the level and duration of action of the neurotransmitter acetylcholine.

Cholinesterase inhibitors have been used with some success to treat Alzheimer’s disease and dementia symptoms. The Alzheimer’s Association notes that three cholinesterase inhibitors are commonly prescribed:

  • Donepezil (Aricept) is approved to treat all stages of Alzheimer’s.
  • Rivastigmine (Exelon) is approved to treat mild to moderate Alzheimer’s.
  • Galantamine (Razadyne) is approved to treat mild to moderate Alzheimer’s.

Most current cholinesterase inhibitors are derived from compounds found in terrestrial plants. For example, Boswellia trees and shrubs grow in West Africa and have an outer bark that peels in parchment flakes, a greenish inner bark, watery aromatic resins and wood with milky latex. Frankincense is the oleogum resin harvested from Boswellia latex. Frankincense has been used as incense since ancient times as medicine and cosmetics. Frankincense provides anti-inflammatory, sedative, anti-hyperlipidemic, and antibacterial activities in Unani (Islamic) and Chinese traditional medicines. The current cholinesterase inhibitors are expensive to produce.

Cholinesterase inhibitor molecule

Cholinesterase inhibitor molecule

Paul Gorham and Wayne Carmichael reported finding anticholinesterase in the cyanobacteria Anabaena, blue-green algae, in 1988. Their focus on the compound was as an algae toxin.

Anticholinesterase has the potential to be helpful in Alzheimer’s disease and may find usefulness as an ASD medication. These compounds are used medicinally to increase neuromuscular transmission in myasthenia gravis patients, treat glaucoma, increase chances of lucid dreaming (by prolonging REM sleep and treat cognitive impairments in patients with schizophrenia.

In neurodegenerative conditions, cholinesterase inhibitors are used to treat the cognitive memory and learning deficits symptoms of dementia. These symptoms are attenuated due to the role of acetylcholine in cognition. Some evidence suggests they may attenuate psychotic symptoms, especially visual hallucinations, in Parkinson’s disease.

A 2015 article describes the screening and purification of cholinesterase inhibitors from marine macroalgae, seaweed. Several lines of studies have provided insight into biological activities and neuroprotective effects of marine macroalgae including antioxidant, anti-neuroinflammatory, cholinesterase inhibitory activity and the inhibition of neuronal death.

While algae bioproducts may moderate developing and aged brains, algae nutraceuticals and medicines are already recommended for treating infants, adolescents and adults with brain problems such as autism and ADHD.

Medical research on early brain development has demonstrated the high value of the long chained polyunsaturated fatty acids, eicosapentaenoic acid, (EPA) and docosahexaenoic acid, (DHA). These nutraceuticals, often marketed as fish oil, come from the fish diet of algae. Several companies culture algae and extract the omega-3s for the nutraceutical industry.

Omega-3 fatty acid supplements have been shown in several studies to moderate the symptoms of autism, ADHD and similar disorders. While these algae compounds do not reverse autism, they essentially moderate the thunderstorm disturbances in the neurological synapses and brain.

Andrew Stoll at McLean Hospital studied omega-3 fatty acids in bipolar disorder. Dr. Stoll found that patients who took concentrated capsules of omega-3 fatty acids had longer remissions between episodes of mood dysregulation. Joseph Hibbeln at the NIH has published several research studies that note: “In the last century, Western diets have radically changed and we eat grossly fewer omega-3 fatty acids now. We also know that rates of depression have radically increased by perhaps a hundred-fold.”

Captain Hibbeln and team were the first to establish a link among military personnel between low omega-3 levels and suicide risk. Suicide risk was greatest among service members with the lowest levels of DHA, the major omega-3 fatty acid concentrated in the brain.

A recent review has shown omega-3 fatty acids to be useful as add-on therapy in bipolar depression, and has been proposed as a treatment for mood stabilization in patients with ASD. Other studies have shown that omega-3 supplements can decrease hyperactivity in children with ADHD.

Omega-3 fatty acids are natural products and induce no side effects, which makes them a first choice for ASD treatment over pharmaceutical drugs with significant side effects.

Path forward

Additional autism research will uncover mechanisms and pathways that occur in fetal and infant life that are responsible for the development problems. New insights will create the opportunity for new algae-based compounds that better manage and possibly reverse not only autism spectrum disorders but also dementia and Alzheimer’s disease.

Organizations Promoting Bans, Restrictions and Alternatives to Pesticides:

If you have ideas on how algae solutions make our world better, please contact Mark Edwards, Professor Emeritus, Arizona State University, at: